Toy set building block



FIG. 1 is a top perspective view of the toy set building block of my ornamental design;

FIG. 2 is a bottom perspective view thereof;

FIG. 3 is a right front elevational view thereof;

FIG. 4 is a left front elevational view thereof;

FIG. 5 is a right rear elevational view thereof;

FIG. 6 is a left rear elevational view thereof;

FIG. 7 is a top plan view thereof; and,

FIG. 8 is a bottom plan view thereof. 

The ornamental design for a toy set building block, as shown and described. 